In the art of flexographic printing there is a strong desire to use printing sleeves. Printing sleeves offer better register and faster changeovers than plates that are directly mounted onto a press cylinder. Various imaging systems are used to form images on printing sleeves. For example, computer-to-plate systems (also known as CTP systems) are used to form images on printing sleeves. A plurality of imaged printing sleeves is subsequently provided to a printing press to create various printed articles. Each article typically includes a plurality of images. It is important that the plurality of images be accurately aligned with respect to one another to ensure accurate registration.
One challenge associated with the use of printing sleeves is the need to replace the entire sleeve when one part of the sleeve needs to be changed. Portions of printing sleeves may require replacement for various reasons. For example, various portions of the printable surface of a printing sleeve may require replacement due to wear or damage to those portions. A portion may also be changed because of a desire to change the image content of that portion. When printing plates are directly mounted onto press cylinders, a desired portion can be readily separated and replaced. This is not easily done with printing sleeves, especially with printing sleeves that include continuous printable surfaces. One possible solution is to divide the printing sleeve into a plurality of segments which are mounted onto the press cylinder. However, the registration requirements that are required by a printing operation makes it difficult to replace a given sleeve segment and maintain registration.
There remains a need for a printing sleeve made up of a plurality of segments that can be mounted on and demounted from a print cylinder while maintaining a required registration of the printing operation.
There is also a need for effective and practical methods of making a printing sleeve that includes segments that can be replaced on-press without adversely impacting print registration.